private void IntensitiesDrawing() { intensitiesSpectrum = spectrometer.GetSpectrum(); int length = 100; float max = intensitiesSpectrum[0]; float min = intensitiesSpectrum[0]; for (int j = 0; j < length; j++) { if (intensitiesSpectrum[j] > max) { max = intensitiesSpectrum[j]; } if (intensitiesSpectrum[j] < min) { min = intensitiesSpectrum[j]; } } //You could also call spectrometer.GetSpectrumData() instead, which return a structure with some more information about the spectrum. //If you also need the corresponsing wavelengths for each point, please see above in the initialization section. List <float> intensitiesListSpectrum = intensitiesSpectrum.ToList(); DrawDiagram(intensitiesSpectrum); }